1. Technical Field
The present invention relates to a projector and a method of controlling a projector.
2. Related Art
For example, in JP-A-2007-59281, there is described a projector, which determines that the state of a discharge lamp is faulty in the case in which the lamp voltage is equal to or lower than a reference voltage.
As one of the factors for causing the illuminance of the discharge lamp to drop, there can be cited devitrification. Devitrification is a phenomenon that an inside wall of a light emitting tube of the discharge lamp becomes high in temperature to thereby be crystallized, and thus get clouded. Since the light transmittance drops in the devitrified part of the light emitting tube, as a result, the illuminance of the discharge lamp drops.
The devitrification occurs irrespective of the value of the lamp voltage. Therefore, it is difficult to detect that the devitrification has occurred by detecting only the value of the lamp voltage as in the projector described above. Therefore, the deterioration state of the discharge lamp cannot correctly be figured out, and thus the product life of the discharge lamp degrades in some cases.